1、 ETSI TS 102 024-2 V4.1.1 (2003-09)Technical Specification Telecommunications and Internet ProtocolHarmonization Over Networks (TIPHON) Release 4;End-to-end Quality of Service in TIPHON Systems;Part 2: Definition of Speech Quality of Service (QoS) ClassesETSI ETSI TS 102 024-2 V4.1.1 (2003-09) 2 Ref
2、erence DTS/TIPHON-05012R4 Keywords E-Model, internet, IP, network, quality, QoS, service, telephony, VoIP ETSI 650 Route des Lucioles F-06921 Sophia Antipolis Cedex - FRANCE Tel.: +33 4 92 94 42 00 Fax: +33 4 93 65 47 16 Siret N 348 623 562 00017 - NAF 742 C Association but non lucratif enregistre l
3、a Sous-Prfecture de Grasse (06) N 7803/88 Important notice Individual copies of the present document can be downloaded from: http:/www.etsi.org The present document may be made available in more than one electronic version or in print. In any case of existing or perceived difference in contents betw
4、een such versions, the reference version is the Portable Document Format (PDF). In case of dispute, the reference shall be the printing on ETSI printers of the PDF version kept on a specific network drive within ETSI Secretariat. Users of the present document should be aware that the document may be
5、 subject to revision or change of status. Information on the current status of this and other ETSI documents is available at http:/portal.etsi.org/tb/status/status.asp If you find errors in the present document, send your comment to: editoretsi.org Copyright Notification No part may be reproduced ex
6、cept as authorized by written permission. The copyright and the foregoing restriction extend to reproduction in all media. European Telecommunications Standards Institute 2003. All rights reserved. DECTTM, PLUGTESTSTM and UMTSTM are Trade Marks of ETSI registered for the benefit of its Members. TIPH
7、ONTMand the TIPHON logo are Trade Marks currently being registered by ETSI for the benefit of its Members. 3GPPTM is a Trade Mark of ETSI registered for the benefit of its Members and of the 3GPP Organizational Partners. ETSI ETSI TS 102 024-2 V4.1.1 (2003-09) 3 Contents Intellectual Property Rights
8、4 Foreword.4 Introduction 4 1 Scope 5 2 References 5 3 Definitions and abbreviations.6 3.1 Definitions6 3.2 Abbreviations .6 4 Definition of TIPHON Speech QoS classes.6 5 TIPHON speech QoS performance metrics .7 5.1 Overall transmission quality rating 7 5.2 Listener speech quality of TIPHON systems8
9、 5.3 End-to-end delay 8 Annex A (informative): Bibliography.9 History 10 ETSI ETSI TS 102 024-2 V4.1.1 (2003-09) 4 Intellectual Property Rights IPRs essential or potentially essential to the present document may have been declared to ETSI. The information pertaining to these essential IPRs, if any,
10、is publicly available for ETSI members and non-members, and can be found in ETSI SR 000 314: “Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in respect of ETSI standards“, which is available from the ETSI Secretariat. Latest updates are available on t
11、he ETSI Web server (http:/webapp.etsi.org/IPR/home.asp). Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web server) whic
12、h are, or may be, or may become, essential to the present document. Foreword This Technical Specification (TS) has been produced by ETSI Project Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON). The present document is part 2 of a multi-part deliverable covering end-to-e
13、nd Quality of Service in TIPHON systems, as identified below: TR 102 024-1: “General aspects of Quality of Service (QoS)“; TS 102 024-2: “Definition of Speech Quality of Service (QoS) Classes“; TS 102 024-3: “Signalling and Control of end-to-end Quality of Service“; TS 102 024-4: “Quality of Service
14、 Management“; TS 102 024-5: “Quality of Service (QoS) measurement methodologies“; TR 102 024-6: “Actual measurements of network and terminal characteristics and performance parameters in TIPHON networks and their influence on voice quality“; TR 102 024-7: “Design guide for elements of a TIPHON conne
15、ction from an end-to-end speech transmission performance point of view“; Part 8: Void; TS 102 024-9: “Call performance Classification (Voice)“; Part 10: To be published as part of release 5 (see note) “QoS Requirements for TIPHON Terminals“; Part 11: To be published as part of release 5 (see note) “
16、Domain by domain performance planning guidelines for end-to-end QoS objectives associated with TIPHON speech QoS classes“; TS 102 024-12: “IP Telephony Service Availability“. NOTE: Quality of Service aspects of TIPHON Release 5 systems will be covered in TS 102 025 (see bibliography), and more compr
17、ehensive versions of the Release 4 documents listed above will be published as part of Release 5 as work progresses. Introduction The present document forms one of a series of technical specifications and technical reports produced by TIPHON Working Group 5 addressing Quality of Service (QoS) in TIP
18、HON Systems. ETSI ETSI TS 102 024-2 V4.1.1 (2003-09) 5 1 Scope The present document defines five classes of Quality of Service for characterizing the speech performance of TIPHON compliant IP voice telephony networks. The classes of service apply to all the defined TIPHON Scenarios and are specified
19、 in terms of the following parameters: “Overall transmission quality rating“; “Listener speech quality“ (one-way non-interactive speech quality); and “End-to-end delay“. 2 References The following documents contain provisions which, through reference in this text, constitute provisions of the presen
20、t document. References are either specific (identified by date of publication and/or edition number or version number) or non-specific. For a specific reference, subsequent revisions do not apply. For a non-specific reference, the latest version applies. Referenced documents which are not found to b
21、e publicly available in the expected location might be found at http:/docbox.etsi.org/Reference. 1 ETSI EN 300 961: “Digital cellular telecommunications system (Phase 2+) (GSM); Full rate speech; Transcoding (GSM 06.10 version 7.0.2 Release 1998)“. 2 ETSI EN 300 726: “Digital cellular telecommunicat
22、ions system (Phase 2+) (GSM); Enhanced Full Rate (EFR) speech transcoding (GSM 06.60 version 7.0.2 Release 1998)“. 3 ETSI TS 102 024-5: “Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; End-to-end Quality of Service in TIPHON Systems; Part 5: Quality of Servic
23、e (QoS) measurement methodologies“. 4 ITU-T Recommendation G.107: “The E-Model, a computational model for use in transmission planning“. 5 ITU-T Recommendation G.109: “Definition of categories of speech transmission quality“. 6 ITU-T Recommendation G.711: “Pulse code modulation (PCM) of voice freque
24、ncies“. 7 ITU-T Recommendation G.726: “40, 32, 24, 16 kbit/s Adaptive Differential Pulse Code Modulation (ADPCM)“. 8 ITU-T Recommendation P.310: “Transmission characteristics for telephone-band (300 Hz to 3 400 Hz) digital telephones“. 9 ITU-T Recommendation G.114: “One-way transmission time“. ETSI
25、ETSI TS 102 024-2 V4.1.1 (2003-09) 6 3 Definitions and abbreviations 3.1 Definitions For the purposes of the present document, the following term and definition apply: codec: combined speech encoder and decoder 3.2 Abbreviations For the purposes of the present document, the following abbreviations a
26、pply: EFR Enhanced Full Rate FR Full Rate GSM Global System for Mobile communications IP Internet Protocol ITU International Telecommunication Union ITU-T ITU Telecommunication standardization sector (former CCITT) PSTN Public Switched Telephone Network QoS Quality of Service 4 Definition of TIPHON
27、Speech QoS classes Three classes of end-to-end speech QoS are defined for TIPHON systems. The following TIPHON speech QoS classes are defined from mouth-to-ear and therefore include both the network and the TIPHON terminal characteristics: WIDEBAND: this is a type of IP telephony service will provid
28、e a user experience better than the PSTN. It is expected that these systems will be implemented using wideband codecs (codecs encoding analogue signals with bandwidth in excess of 3,1 kHz) and QoS-engineered IP networks; NARROWBAND: this is a type of IP telephony service will provide a user experien
29、ce similar to PSTN. It is expected that such systems would also be implemented over QoS-engineered IP networks: - NARROWBAND/HIGH: this quality is equivalent to recent ISDN services; - NARROWBAND/MEDIUM: this quality is equivalent to recent wireless mobile telephony services in good radio conditions
30、, for instance GSM networks using EFR codecs (see EN 300 726 2), or systems using ITU-T Recommendation G.726 7 at 32 kbit/s codecs; - NARROWBAND/ACCEPTABLE: this quality is equivalent to common wireless mobile telephony services, for instance GSM networks using FR codecs (see EN 300961 1) or systems
31、 including a geostationary satellite. BEST EFFORT: this type of service will provide a usable communications service but will not provide guarantees of performance. There may be periods of significantly impaired speech quality, and large end-to-end delays which are likely to impact the overall conve
32、rsational interactivity. It is expected such communications will operate over non QoS-engineered IP networks such as the public Internet. The TIPHON speech QoS classes WIDEBAND and NARROWBAND will provide performance guarantees for 95 % of all connections. The BEST EFFORT class provides no speech pe
33、rformance guarantees. ETSI ETSI TS 102 024-2 V4.1.1 (2003-09) 7 5 TIPHON speech QoS performance metrics Each of the classes defined in clause 4 is specified by three performance metrics: Overall transmission quality rating (R); Listener speech quality (One-way non-interactive end-to-end Speech Quali
34、ty); and End-to-end (mean one-way) delay. To comply with a specific speech QoS class a TIPHON system shall meet the limits of “Overall Transmission Quality Rating R“ given in table 1. In addition the limits of “End-to-end Delay“ and “Listener Speech Quality“ given in tables 3 and 4 respectively shal
35、l be met in the very same class. NOTE: The measurement of “Overall Transmission Quality Rating (R)“, “Listener Speech Quality“ and “End-to-end Delay“ are described in TS 102 024-5 3. 5.1 Overall transmission quality rating Overall transmission quality rating (R) describes the full acoustic-to-acoust
36、ic (mouth to ear) quality, experienced by an average user, for a typical situation using a “standard“ telephony handset. The overall transmission quality rating is calculated using the E-Model (ITU-T Recommendation G.107 4). For calculation purposes the use of traditional telephone handsets (ITU-T R
37、ecommendation P.310 8) at both sides of the connection is assumed. Table 1: Overall transmission quality Rating (R) for TIPHON systems 2 (NARROWBAND) 3 (WIDEBAND) 2H (HIGH) 2M (MEDIUM) 2A (ACCEPTABLE) 1 (BEST EFFORT) Overall Transmission Quality Rating (R) (see note 2) 80 70 50 50, (see note 3) NOTE
38、 1: The R-value incorporates all degradations, including the effects of packet loss. NOTE 2: The R-value characterization of systems employing wideband codecs is under study. NOTE 3: The rating for the best effort class is a target value. NOTE 4: The speech quality levels given in the present table
39、shall apply for a percentage of the duration of a call. The percentage of the duration when speech quality falls below the specified levels and the distribution and duration of the intervals when this occurs is for further study. NOTE 5: The percentage of occasions that a requested (or contracted) s
40、peech quality level is not available for any reason is a Grade of Service issue and is a matter of policy for individual service providers. NOTE 6: What happens if a requested or contracted QoS level is not available is subject to the policies of individual service providers. The relation between ov
41、erall transmission quality rating (R) and user perception of quality is defined in ITU-T Recommendation G.109 5. Table 2 is extracted from this recommendation. Table 2: Categories of speech transmission quality as defined in ITU-T Overall Transmission Quality Rating 90 R 86 73 50 50 NOTE 1: The R va
42、lues above are derived from E-Model calculations assuming that perfect echo control is deployed, that there is zero delay through the system, that standard terminals are used, also that all impairments related to low bit-rate coding - including the effects of packet loss - are taken into account. NO
43、TE 2: “Relative speech quality“ does not describe the Listener Speech Quality (the full acoustic-to-acoustic (mouth to ear) quality that will be experienced by a user). This will be dependent on the acoustic quality of the individual TIPHON terminal as well as the quality of the TIPHON network. NOTE
44、 3: The use of codec examples indicates a relative speech quality, not a recommended codec for implementation. The performance levels include any degradation caused by network or terminal, such as packet loss. NOTE 4: The speech quality levels given in the present table shall apply for a percentage
45、of the duration of a call. The percentage of the duration when speech quality falls below the specified levels and the distribution and duration of the intervals when this occurs is for further study. NOTE 5: The percentage of occasions that a requested (or contracted) speech quality level is not av
46、ailable for any reason is a Grade of Service issue and is a matter of policy for individual service providers. NOTE 6: What happens if a requested or contracted QoS level is not available is subject to the policies of individual service providers. 5.3 End-to-end delay Specifications of end-to-end (m
47、ean one-way) delay for TIPHON QoS classes are based on ITU-T Recommendation G.114 9 and are given in table 4. Table 4: End-to-end delay for TIPHON Systems 2 (NARROWBAND) 3 (WIDEBAND) 2H (HIGH) 2M (MEDIUM) 2A (ACCEPTABLE) 1 (BEST EFFORT) End-to-end Delay 100 ms 100 ms 150 ms 400 ms 400 ms NOTE 1: The
48、 delay for best effort class is a target value. NOTE 2: The speech quality levels given in the present table shall apply for a percentage of the duration of a call. The percentage of the duration when speech quality falls below the specified levels and the distribution and duration of the intervals
49、when this occurs is for further study. NOTE 3: The percentage of occasions that a requested (or contracted) speech quality level is not available for any reason is a Grade of Service issue and is a matter of policy for individual service providers. NOTE 4: What happens if a requested or contracted QoS level is not available is subject to the policies of individual service providers. ETSI ETSI TS 102 024-2 V4.1.1 (2003-09) 9 Annex A (informative): Bibliography ETSI TS 102 025 series: TIPHON Release 5 QoS documents. ET
